Is the Helicon Remote for the iPhone capable of doing focus stacking?
I can focus in and out with the > >> and >>> arrows but there doesn't seem to be the other controls like the Helicon Remote laptop/computer software.

It would be great to control the camera for focus stacking out in the field when doing macrophotography.

I'm not sure what you mean. The mobile app has all the same functions as the Windows/Mac program. Did you notice the Exposure / Focus / Live View / Tools tabs? For example, the Focus tab has the same interface for setting up automated exposure stacking as the Windows/Mac version of the program.

Oh, i can agree the observed behavior of focus bracketing with the EOS 80D and EOS 5D MK4. I also have found out that the camera manualy move the lense focus as expected. If i fix start end endpoint and let the lense move from a to b without capture a picture - it lost steps. Each next move, the same count of steps are lost. The bebining position will not reached. The next move to the endpoint, it moves exactly this 5 steps over the endpoint and adds the 5 more steps. I can reproduce this issue with an bunch of tested lenses. In regular case, this are a Sigma 60mm f/2 DG Macro and the sigma 105mm f/2.8 DG OSM Macro. I had attempt to use a sigma 50mm f/1.4 Art using an 10mm adapter ring. This lense is quite fast and very new.
I don't use them for macross but this should confirm my observations.
If i fix the start and endpoint again, set around 10 Steps between start and end, move to start and begin capture, the linse attempt to move to the next point, stops, and move back. Every picture looks similar. The cam is set in Manual mode and the autofocus in ONE-SHOT - not AI or every trace mode. The cam is linked by an USB-Cable.
I am not able to find out where the problem is. Actualy i had ordered a focus rail (Novoflex) to solve this issue as long as this behavior is fixed.
The compatiboility list seems not cover every available functions of Helios Remote.
If you have any idea, let me know what i need to do that this not happens.

Do you get the same issues with Canon lenses? I'm not saying that this the case here but there have been focus issues with Sigma lenses for years. They have to try to reverse engineer all the focusing data.

Yes, similar situation with all the lens i have - Sigma60mm, Canon MPE65, Sigma 105mm, and canon ef100mm macro.
The lense does, what the camera says. It looks as would the camera move the lense to the next position and the autofocus move them back. It just walk just one step, and moved back immediate. This happens on both cameras. The same check with an older EOS600D and the same lenses works proper. I had done the tests using USB - wifi if possible.

MPE is true without a focus motor. The issue is, that the program does'nt notice that at an 80d and 5D Mark4. If an EOS 600D is used, the usage of the MPE will response with an error message in Helicon Remote. This let me further assume that their must be something more different as just implemented some new features in the OS of those canon camera models. Actually i had not found any user of this cams who has succesfully done this way of focus bracketing.
However, i am just a little disappointed with the compatibility statement of both Helicon cameras, without restrictions. Since the developers were probably a little too optimistic and I doubt that they have ever tried this combination. My lenses works pretty in combination with an EOS 600d.

I think it's good that you can try out the software beforehand. Why I can not record RAW images with the trial version, I think as an additional limit even more unprofessional. An assessment of image quality is so difficult. It is a pity but not to change.

Well, i need now to find a working alternative to Helicon. As now, i went me back to a Novoflex Castel-L Rail and manual focus moving. It's just need more time.

We've tested focus stacking with 80D and have detected some discrepancies, but it's unclear whether it's a software issue or if the lens is mechanically unable to carry out focus movements with sufficient precision. We're looking into it.

Oh well, i had additionaly tested the Canon 180mm f/2.8 L today with the same result with the 80D and 5D MK4.
I assume that this is a different focus handling of the bodies. The lenses are always the same tested on different bodies i checked as now.
I looks like, that the lense move a step forward and immediatly moves back. The command from the host to the camera to move forward is received and executed successfully. The bodies will immediate response the focus moving with a start of autofocus procedure again.
I would more to investigate in the direction, if it's maybe possible that the new bodies maybe needs to received an extra command like
"autofocus off" previously the step command is releases. I had not found any setting in the bodies software setup menu, where this could be manualy deactivated. This could be works like switch the lenses autofocus off. Unfortunatly, this way does'nt work because some lenses release the focus motor gear and disconnect the focus motor. I also had checked the advanced options in the 80d and 5Dmk4 to find an option who just deactivates just the autofocus function with now luck. If i can help's you more, let me know this.

We can't reproduce the focus returning back after a focus step is performed. Our 80D does not exhibit this behavior with our USM lens. I don't believe this is a programmatic problem on our part.
There are, however, some focus movement oddities that we will be looking into.

Well, it's would be a good idea to know, what kind of lenses you had testet with your 80D. In addition, a detailed description of your Setup would take clear it.
As i understand, the lense does not initiate a re-focus operation. The body control the lense, not the lense the body. Followed this assumption, why should a lense focus motor init a move-back, even the body will not send this command?
And in addtion, the lenses i had testet on "older Bodies" where all the same and all of the are work as expected. I assume that the newer body will be the root of the issues.

Focus issues with Sigma lenses mostly are front- or back-focus related. Sigma lenses are often got other optics than canons lenses. The problem of them and other third-parties is, that they are not supported by the bodies firmware and the API of the firmware an the communication protocols are unavailabe. The optic are often better and cheaper than canon and the third-parties do a good job, that the selled devices are works proper.
Helicon is also one of this third-party and i guess that they are not supported by canon, too. In my case, my checked Canon L Lenses don't work too.

Canon is responsible for all changes and lately responsible for the issues, not Helicon or Sigma. I aggree so far in this statement, but this will not helps any further.

I am sure that the bodies firmware are responsible for the issues and not the lenses or helicon remote software. I don't expect that the behavior is different on the Android or Apple APP.

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An additional observervation of my actual running test with the EOS80D and Sigma EX 70mm f/2.8 DG Macro could be interessting to find out where the issues related to.

Helicon Remote connected to a Canon EOS 80D

helicon.JPG (61.12 KiB) Viewed 3656 times

If the DOF Preview option is unflagged, the focus will not work, the focus moves undefined, both fixed focus points are getting wrong. If the function is selected again, the Point A & B are fix and i can moved the fokus between both points by using the arrows, without lost steps!! I had prevently expand the inter-Stepping wait time from 200ms to 400ms, to give the Stepper motor more time to move the lense group - this lens is a "grandmom". Everything is looking good, until i "start shooting". Immediately i do this, everything is went wrong. At first, the fokus is moved out of any sharpness, moves anywhere and undefined in the hole available focus range of the lense. It's impossible to stop this by using the software - need to switch-off the body. It look's funny anyway. I don't know where the different is, using the the steps manually by the arrows, and later the moving by the software and doing a picture.
Capture a single picture using the button "take picture" works as expected. The focus will be unchanged.

Thanks for the info, we'll be further testing focus stacking with DOF Preview enabled - hopefully, the problems during focus stacking process occur because we're doing something wrong with DOF Preview - perhaps, we're turning it off when we shouldn't. If so, we'll fix it.

We've tested 80D with Canon EF 24-70mm f/2.8L USM and with Canon EF-S 17-85mm f/4-5.6 IS USM lenses, with and without DOF Preview, and we did not observe any of the weirdness that you've described. We did observe minor focus drift, and also some occasional hiccups/lost steps that should occur and that we will be looking into (although so far we can't find anything wrong in our programming in that regard).
So, it's not that the 80D body just handles focus commands differently. So far it seems that the problem only occurs with 80D and a Sigma lens, not with Canon lenses. Do you have any Canon lens?

So, it's not that the 80D body just handles focus commands differently. So far it seems that the problem only occurs with 80D and a Sigma lens, not with Canon lenses. Do you have any Canon lens?

Well, the 80D does handle the focus workflow internaly different as the models before. I got this information from a developer of a medical solution who uses the 80D in combination with a newer endoscope, that the company develop he work for. He could'nt tell me the details because an non-discloser agreement he must sign.
He told me that the newer EOS needs to be switched into a manual focus mode previously you send a stepper command for the focus move. This must be different as before. Is it?
The body does'nt have such menu entry or function key who do this. I had seen that the canon eos utility has a button doing this.

In addition, their must be some newer commands availale who are not describted in the EDSDK and some monitor-Messages (what ever this means) must be handled too. I am not sure if this is related to the focus issue. I am not know'n him personaly and i woul'nd ask him further about the details but the gives a some interessted points where i need to do some further investigations.

I had wrote canon to ask tabout a permission to download the edsdk as a basis for some test with the usb / EOS80 handling. Sniffing the USB without the basic knowledge about the handling of the used PTP Protocol will not help's.

The sigma Lenses:
The focus motors of the lense can be to slow - that's happen's if an older stepper motor is used instead modern HSM. That's can be solved by using an time delay between the steps, that i had checked.

No, the program will not stop working.
Interesting info about firmware differences of the 80D from previous Canon cameras, we'll keep this in mind. Still, as I said, so far we weren't able to observe these differences.
Have you tried switching the lens to manual mode? Have you tried this with the Canon lenses on a 80D?

Well, i guess i had found the source of the issue. The phonecall was quite helpful to walk in the right direction. he had absolutly right that the internal workflow must be changed.
I wrote me a very tiny application who just connect the body, init the handlers, readout the camera's vendor-id, model, serial-Nr and some other info.

A simple loop who just send the sequence: "set liveview on -> step forward 3 steps -> set manual focus -> set Capture_full (not halfway) -> delay 200ms". If the loop counter reached 24 ,end the loop " move back 24 steps -> release the mirror-> close usb.
The back-move of the focus from the destination back to the start point is build by a second loop.
Some variation will be checkt too if there is a different behavior or not.

I had unexpectly found out, that canons EDSDK requires to read the camera's model and id before any further task will be done. I guess that they dispatch the used command sets for the different methodes they had implemented in the bodies. An USB-Dump will get clear what they send to the different bodies.

I expect that the canon 5DMk4 will work too. If so, i will ask my frend about the eos 600D to prove, if this works also on that model.

That's the quick description of the process.

This example works with every lense, Canon and Sigma, older and newer, i had checked on the EOS 80D. at the weekend if a spare time is left, if will do this in combination with the EOS 5D Mark4.

unexpectly, the oldes lene Sigma 70mm f/2.8 DG Macro uses a micromotor - but don't lost steps even i move ove 30 steps forward and backward 4 times. This surprised me, the 200ms interstep delay is a short time for that.

I had done a picture set and stacked them in affinity photo and thsi seems to be ok so far. It's not an art, just to check the methode.

Additionally i will attempt to find out how the method works to read-out the shutter- and mirrorcount. An USB dump is available of a working tool who do this successfuly. This API seems to set a debug mode option on (MonOpen, MonReadAndGetData, MonClose) to get this info.